1. Field of the Invention
An engine (an internal combustion engine) for a vehicle is provided with an air cleaner for intaking a cleaned air.
This invention relates to an intake device for an internal combustion engine, which helps a function of air cleaner provided for intaking cleaned air.
2. Description of the Prior Art
Usually, since an engine provided in an engine room of a vehicle is set in a unit with an air cleaner and covered with a bonnet, the cleaned air is adapted to be supplied avoiding the influence of wind or rain. Further, such air cleaner is provided with a drain hole of 5 mm in diameter and such on the bottom thereof. Thereby, even if moisture inside the air cleaner is condensed, it is drained therethrough to prevent others from coming through the air cleaner.
As one example, as shown in FIG. 7, in a vehicle of the type in which an engine room 1 is disposed at the front side of the vehicle body, an air intake 2a of an air cleaner 2 faces to a side panel 3, to which an air inlet pipe 4 is connected, and in communication with a suction pipe 6 in a fender. Further, the suction pipe 6 is provided with a cavity resonator 7. More, at this section alternatively, a suction case which is formed in a unit with the suction pipe 6 and the cavity resonator 7 may be disposed.
Further, the suction pipe 6 and the air cleaner 2 are mounted through a vibration insulator rubber (it is called floating) to prevent a vibration due to an intake pulsation from being transmitted to a vehicle. Here, a sign 8 shows a drain hole (refer to Japanese Utility Model laid-open Nos.
Hei 5-62316 and 5-24948) and a sign 9 shows an outer fender.
In the above structure, the air which is supplied to an engine is sucked in from a suction pipe 6 goes through the air suction inlet 2a of the air cleaner 2, a suction opening 2b, an inlet pipe 10 and a surge tank (not shown).
And as shown in FIG. 6, there is an idea which a Z-letter like suction pipe (or air inlet pipe) 6 is connected to the air cleaner 2 through the air inlet pipe 4 to reduce a suction noise. The Z-letter suction pipe 6 is mounted on a fender 5 and fixed to it in several portions using a bolt 11, collars 12 and cushion rubbers 13. Further, signs 6a and 2c are mounting stays.
Normally, when the rotation number of an engine is increased, the shaft rotation connected through a transmission is also increased and as a result, the vehicle speed is increased. Then, since a negative pressure inside the air cleaner as well as an air suction pressure becomes larger, at the time of raining or snowing, water drops entered from outside become apt to be sucked from the drain hole. When the water drops are attached to an element in the air cleaner 2, a passage to the suction pipe 10 becomes substantially narrow and the sucked air is likely to lose a sufficient supply of the air to an engine. Further, since it is not convenient to open a bonnet for regulating various devices at the time of such weather condition, the regulating devices have to be provided inside the vehicle.
On the other hand, since the air inlet pipe 4 is mounted through the cushion rubber in a floating manner and connected to the suction pipe 6, a number of mounting process not only is increased but also becomes complicated, in addition, parts are increased in number. Further, in the case of the suction pipe 6 shown in FIG. 6, where it is mounted on the fender 5 through the cushion rubber 13 and connected to the air cleaner 2, the number of working process is increased and the working becomes complicated.
In the present invention, the purpose of it is to provide an intake device in which a construction of an inlet pipe connected to an air cleaner and a suction pipe are simplified and the outer water drops are prevented from entering through a drain hole.
To attain the above object, the invention described in claim 1, an air inlet pipe connected to an air cleaner in an engine room is extended in such a manner as it surrounds the outside space of a drain hole which is provided at the bottom of air cleaner.
Further, in the invention described in claim 2, in the above construction, the air inlet pipe is connected to the position outside the drain hole of the air cleaner bottom and extended and curved downward.
Further, in the invention described in claim 3, in the structure of claim 1, the air inlet pipe is arranged along a side panel and between the side panel and the air inlet pipe a cushion is interposed.
Further, in the invention described in claim 4, in the construction of claim 1, a body of the air inlet pipe connected to the air cleaner is fixed on the side of the air cleaner in such a manner as it becomes in a unit with the air cleaner, and the air inlet pipe is made apart from the side panel to form it in a floating construction.
In the above construction, since it is for an engine mounted on a vehicle, or engine room is covered with a bonnet and disposed in a front or rear portion of the vehicle. And, since the air cleaner is essential, it does not matter if the engine is arranged horizontally or vertically. Brief explanation of the drawings.